/*
    This file is part of the substandard lisp implementation of Standard Lisp
    Copyright (C) 2011 Nicky Nickell

    substandard lisp is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

function std_errorset(a, env) {
  var u = a[0];
  var msgp = a[1];
  var tr = a[2];

  try {
    return u.evaluate(env);
  } catch(e) {
    if (e.type == ERROR_USER) {
      if (msgp != NIL) {
        env.variables.get('ERROUT*').write('++++ ' + e.value.prin1() + ' ' + e.mess.prin1());
      }
      env.variables.set('EMSG*', e.mess);
      return e.value;
    } else {
      throw e
    }
  }
}

/*---
name: errorset
arity: 3
rest: false
ftype: FTYPE_EXPR

argument-types:
  - CLASS_ANY
  - TYPE_BOOLEAN
  - TYPE_BOOLEAN

doc: |
  explaining what errorset is / how it is used!

tests: |

...*/
